29 January 2016, 10:39
Are councils putting cost savings before environmental benefits?
Around the same time as the introduction of the new legislation for Euro 6 on highway engine emissions was announced, compact road sweepers were declassified from being “on road” vehicles in the UK to “specialist off road vehicles”. This means that off-highway engine emission standards are permitted as opposed to the more stringent on-highway standards. So what is the difference, and how does this affect local authorities?
Well, local authorities now have a choice: they can legally operate Compact road sweepers on the streets with an “off-highway engine” supplied. This is classified as a Stage 3b engine, or termed as a Euromot 3b engine by some suppliers. (Euromot is a European association and not an engine classification.) This is a lower cost engine which, if under 56kW,does not require such an expensive exhaust emissions after-treatment system. The savings can be between 5% and 10% of the capital cost of the vehicle. However, the off-highway engine produces more harmful exhaust emissions, especially NOx gases and hydrocarbons, both of which are harmful to humans and contribute to poor air quality.
The off-highway legislation still has strict environmental standards, and all off-highway vehicles with an engine power output more than 56kW have to meet relatively high emission standards. However, off-highway engines under 56kW have higher allowable emissions and typically are not required to have AdBlue after treatment, NOx sensors or selective catalytic reduction (SCR), which means that sweepers installed with the 55kW engine have emissions far worse than Euro 5 sweepers which many Councils have in operation today.
The difference in emissions is equally as dramatic. The Stage 3b engine will produce up to 87% more harmful hydrocarbons and NOx gases than the Euro 6 engine, and is up to 46% worse than the Euro 5 engines being operated today.
Johnston Sweepers, along with all suppliers of sweepers into the EU, has introduced either the Euro 6 engine and/or the 55kW Stage 3b engine into the compact range. The choice of engine sits with each Council or commercial user. Many European cities insist on Euro 6 engines being supplied, regardless of the legislation, whilst other developing countries in Europe may accept the cheaper but less environmentally friendly Stage 3b engine. The UK appears to still be undecided as to which engine should be supplied.
However, it is worth highlighting that the road sweeper is the only vehicle on the street which collects and traps harmful PM10 (particulate matter less than 10 microns). It seems counterproductive to the environment to have a vehicle which is itself environmentally friendly, being powered by an engine which produces more harmful emissions and which would not meet the previous Euro 5 standard being operated today.
With financial cut backs so high on the agenda in UK authorities it is hard not to look at the bottom line, and a 5% saving can have a significant impact on government funds. But can local authorities really be seen to be replacing Euro 5 sweepers with equipment which is actually less environmentally friendly? So, the question for all municipal operators should be - is my Council putting cost before the environment?